I. IntroductionSleep is of paramount importance in our daily lives. Prolonged lack of sleep can lead to a weakened immune system and, in the worst cases, death. As anyone can understand, our sleep-wake cycle is relatively regular and stable, and there is a reason for our regular biological cycles: the suprachiasmatic nucleus (SCN). In our body, several biological clocks regulate circadian rhythms like our sleep-wake cycle and hormone release rhythms. In the hypothalamus, the suprachiasmatic nucleus (SCN) contains the master clock that regulates the brain's peripheral circadian clocks to prevent them from falling out of sync with each other. The SCN also receives information from the retina about light entrainment and thus keeps the entire system in sync with the light-dark (LD) cycle. The central dogma in the field of circadian biology is that light is the primary zeitgeber, signal that drives the circadian rhythm. Many studies show that daytime SCN neuronal activity and light-induced SCN neuronal activity inhibit locomotor activity in nocturnal rodents. However, several studies show that food anticipatory behavior (FAA), induced by limiting food to a few hours per day, can be a zeitgeber that overrides all other cues, including light. Rodents can anticipate a predictable daily meal time through the entrainment of circadian oscillators. Studies show that this anticipatory behavior does not require the master circadian clock within the SCN, leading to the hypothesis that there are food-entrainable oscillators (FEOs) in the brain responsible for anticipatory behavior. However, the circadian oscillators responsible for FAA are still unknown. In this article I...middle of the article......may not seem practical, it might shed some new light on where OEMs are located. Furthermore, more tests need to be performed using different clock genes to determine whether DMH is actually involved in FAA or simply downstream of other circadian oscillators that determine FAA. If there are indeed several OEMs at play, as proposed by Feillet et al. (2008), it is then necessary to carry out experiments combining lesions in several sites to produce alterations in the FAA (Feillet and Mendoza, 2007). Again, because the answer is open to endless possibilities, I also participated in the research to locate OEMs. However, my results yielded no significant rhythms in the DMH when we performed in situ hybridization targeting the clock gene Baml1. Reading these articles, perhaps a future research direction, even for me, will consider other OEMs than DMH..